The present invention relates to a method for optimizing the take-off parameters of an aircraft and, in particular, a system for automatically controlling the high lift devices of an aircraft during take-off.
Such a control system for the high lift devices (namely slats and/or flaps) of the aircraft comprising actuation means for moving the high lift devices, a control unit for controlling the actuation means and a means for detecting the actual take-off of the aircraft, corresponding to the moment when the wheels of the aircraft leave the ground, are already known from the patent document FR2817535. At the start of the take-off phase, the high lift devices are brought into a first position in which they are deployed and the control unit is configured so as to generate, at least when the means signals the actual take-off, a control command making it possible to bring the high lift devices into a second position in which they are retracted relative to the first position.
With such a system, during the take-off phase: as long as the aircraft is rolling on the ground, the high lift devices are deployed so as to increase the lift of the aircraft, which has the effect of reducing the take-off speeds and therefore reducing the runway length necessary for the take-off. Consequently, for a given type of aircraft, notably a civilian transport airplane, equipped with such a control system, it is possible to either increase its weight, or use a shorter take-off runway, by comparison to an aircraft of the same type not provided with the control system; and when the actual take-off takes place, that is to say when the wheels of the aircraft leave the ground, the high lift devices are brought into a less deployed position (that is to say with less high lift) so as to reduce the drag, which makes it possible to then obtain an increased climb slope (considering a possible failure of an engine) allowing for a take-off in complete safety.
Although such a system is satisfactory and makes it possible to reduce the take-off length, the aim of the present invention is to enhance this system in order to increase the weight that can take off and consequently the degree to which the aircraft may be filled.